1. Field of the Invention
This invention relates to a powdery pharmaceutical composition for nasal administration. More specifically, this invention relates to a powdery polypeptide or its derivative composition for nasal administration which comprises physiologically active polypeptide or its derivative such as calcitonin, insulin, etc. and a water-absorbing and water-insoluble base and allows said polypeptide or its derivative to be effectively absorbed through the nasal mucosa when nasally administered.
2. Description of the Prior Art
Because of the fact that peptide hormones such as insulin, calcitonin, etc. have a high molecular weight and that they are readily decomposed by proteolitic enzymes such as pepsin, trypsin, chymotrypsin, etc., the peptide hormones are not absorbed sufficiently enough to display a pharmacological effect efficaciously and accordingly they have been administered by parenteral injection.
However, since the administration by injection causes pain, various attempts to develop alternative methods of administration have been made. For example, there is a method of intrarectal administration of a suppository prepared by use of such salicylic acid derivatives as sodium salicylate, 3-methoxy sodium salicylate, and 5-methoxysalicylic acid as an absorption aid (J. Pharm. Pharmacol., 33, 334, (1981)). Besides this method, a method of intrabronchial administration (Diabetes, 20, 552, (1971)) and a method of eye-dropping administration (Diabetes Society's Epitomes, 237, (1974)) have been studied.
There are, however, drawbacks to all of these methods in that they require much larger doses than injection and that their absorption is varied and accordingly any of them have hardly been put to practical use as yet.
On the other hand, there is a method of nasal administration of an acidic aqueous solution of insulin, wherein such a surface active agent as sodium glycocholate is used as an absorption aid, known as the attempt to develop a method of intranasal administration (Diabetes, 27, 296, (1978)).
However, this method may not be regarded as an expedient means, since the preparation is prepared in the form of a liquid often causing the drug to flow out of the nasal cavity upon its administration into the nose and the use of a surface active agent in its preparation also causes inconvenience.
As the powdery pharmaceutical composition for nasal administration, U.S. Pat. No. 4,294,829 discloses a pharmaceutical preparation comprising lower alkyl ether of cellulose and a drug. This pharmaceutical composition is characterized in that its lower alkyl ether of cellulose absorbs moisture on the nasal mucous membrane, and takes the form of a viscous liquid to slowly flow over the nasal mucosa and releases the drug slowly. Since the composition of this type takes the form of a viscous liquid in the nasal cavity, the drug with a high molecular weight tends to stay within the lower alkyl ether of cellulose, becoming reluctant to the release from the composition. The composition of this type should, therefore, still undergo a significant improvement if it is to use such a drug with a high molecular weight as calcitonin, insulin, and the like.